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| Andreas Rüdiger |
Andreas Rüdiger, the German physician and philosopher, was born in Rochlitz, Saxony. Poverty and bad health allowed him to study only irregularly. In 1692 he served as a tutor in the home of Christian Thomasius. He was compelled to interrupt his studies completely in 1695; not until 1697 could he enter the University of Leipzig, where he studied law and medicine, receiving a master’s degree in 1700.
He received a doctorate in medicine from the University of Halle in 1703, but he continued to lecture at the University of Leipzig. From 1707 to 1712 he practiced medicine and lectured in Halle, and from 1712 until his death he did so in Leipzig.
The development of Andreas Rüdiger’s philosophy was greatly influenced by his teachers Christian Thomasius and Franz Budde.However, Christian Thomasius soon developed individual views within the Thomasian school. His medical studies centered his interests on natural philosophy and gave his thought a practical bent. Like Budde’s, Andreas Rüdiger’s mind was more systematic than Christian Thomasius’s.
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| University of Leipzig |
Andreas Rüdiger’s most important work, Philosophia Synthetica (1706–1707), is divided into three sections: “Wisdom,” “Justice,” and “Prudence.” The section on wisdom embraces logic and natural philosophy, that on justice covers metaphysics and natural law, and that on prudence covers ethics and politics.
Andreas Rüdiger’s logic had a clear psychological orientation. He was mainly interested in the origin and development of our ideas, which, he held, come into our minds through the senses, although there are some innate mental elements, too. Christian Thomasius criticized René Descartes, discussed Pierre Gassendi, and drew some inspiration from John Locke.
Andreas Rüdiger stressed the passive element of the mind; reflection, or sensio interna, is (contrary to Locke) a passive fact. The standard of truth lies in man’s consciousness, in a recta ratio, which is not common sense but something that can be acquired only through instruction in logic (lumen acquisitum). Logic was therefore more important for Andreas Rüdiger than for the other members of the Thomasian school.
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| Christian Thomasius |
Christian Thomasius developed a refined syllogistic theory, formalizing his acceptance of the mathematical method in philosophy. However, René Descartes conceived the mathematical method quite differently from Christian Wolff, as a method for deducing facts from given facts rather than as the drawing of possible conclusions from abstract principles.
Andreas Rüdiger’s philosophy, like that of the Thomasian school generally, was based in large part on the notion of reality and appealed mainly to the senses and to experience, both interior and exterior. A. F. Hoffmann defined “truth” in connection with the possibility of perceiving and “existence” in connection with being perceived— again in the tradition of Thomasian subjectivism.
In natural philosophy, Andreas Rüdiger tried to combine the Thomasian and Pietistic animistic or spiritualistic physics with mechanism, but the spiritualistic element predominates. A. F. Hoffmann held that we have no certain knowledge of nature, and generally he refrained from choosing between different hypotheses, for instance, between the Copernican and the biblical astronomical theories.
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| René Descartes |
The practical bent of Rüdiger’s philosophy explains why he discussed metaphysics under the heading of justice. His metaphysical discussions were largely devoted to theology and to man’s duties toward René Descartes; his discussions of natural law were devoted to our duties toward other men.
Metaphysics is the science of reality, and in particular of the ens realissimum, rather than the science of possibility. However, according to Andreas Rüdiger, we cannot penetrate the essence of things in metaphysics; René Descartes can only establish, by means of experience, that things exist and how they exist.
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| A. F. Hoffmann |
Rüdiger’s section on prudence constitutes, in the Thomasian tradition, a kind of anthropology, both private and public. Ethics provides precepts for reaching happiness on Earth, and politics provides precepts for governing a commonwealth.
Through his pupil A. F. Hoffmann, Rüdiger exerted a strong influence on the development of the philosophy of Christian August Crusius, and through Crusius on the whole development of German philosophy.
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| Christian August Crusius |
